1. Technical Field
The present invention relates generally to balloons; and, more particularly, to water grenade balloons and a mold for manufacturing the same.
It is to be understood as the ensuing description proceeds, that the phrase "water grenade balloon" is used herein and in the appended claims in a non-limiting descriptive sense to designate a balloon whose configuration and appearance in both the non-inflated and the inflated state--but, particularly in the non-inflated state--is intended to simulate a grenade which can advantageously be filled with water (i.e., hydraulically inflated), thus leading to its popular designation as a "water grenade balloon"; but, which can also be filled with air (i.e., pneumatically inflated) or helium (i.e., gas inflated) to produce essentially the same characteristics as any other conventional balloon. In short, while the present invention relates to what is descriptively termed a "water grenade balloon", those skilled in the art will appreciate that users of the balloon can choose to inflate it not only with water but, alternatively, with air or gas.
2. Background Art
Conventional prior art water grenade balloons have typically been formed by dipping a balloon mold into a latex bath and thereafter curing the latex and stripping the balloon from the mold. Such a prior art mold is commonly shaped with a generally elliptical surface of revolution described about its major axis; and, includes shallow, intersecting, longitudinal and latitudinal grooves so that the water grenade balloon thus formed includes shallow intersecting longitudinal and latitudinal depressed lines when the balloon is in the uninflated state to simulate the outward appearance of a grenade. Upon inflation, the balloon sidewall assumes a smooth, regular, rounded surface devoid of grooves, but having darkened intersecting longitudinal and latitudinal lines which, although not depressed, continue to simulate, albeit to a somewhat lesser extent, the appearance of a grenade.
Production lines for forming balloons vary from plant to plant and from manufacturer to manufacturer. One conventional prior technique includes, among other steps, dipping the molds into a latex bath while the molds are rotated about their vertical axes and moved laterally or horizontally through the latex bath. In such a conventional system, the mold moves vertically (both into and out of the liquid latex), horizontally and rotationally relative to the liquid latex during the dipping process; and, such a conventional process has been successfully employed to manufacture water grenade balloons using molds of the foregoing type having shallow intersecting longitudinal and latitudinal grooves formed therein. A water grenade balloon made in such a process and using such a mold is depicted in U.S. Pat. No. Des. 301,595-Murray assigned to the Assignee of the present invention.
Another conventional dipping process used in some balloon production facilities involves a latex dipping step characterized by purely vertical relative movement between the mold and the latex bath--i.e., either the molds are lowered into the latex without any relative horizontal or rotational component of motion or, alternatively, the molds are suspended in stationary form while a tank of latex is raised upwardly until the latex surrounds the stationary molds with the tank thereafter being lowered; in either case, a dipping operation devoid of any relative horizontal or rotational component of motion between the liquid latex and the mold. Unfortunately, however, it has been found that when using this conventional dipping process with molds having shallow intersecting longitudinal and latitudinal grooves, the balloons thus formed are characterized by the presence of undesirable pinholes and/or thinned weakened areas of latex which form weakened blisters when the balloon is inflated, such pinholes and weakened areas being formed on or in the linear areas of the balloon's sidewall corresponding to the longitudinal and latitudinal depressed lines formed in the balloon's sidewall when the latex is deposited in the mold's longitudinal and latitudinal grooves. The presence of one or more of such pinholes in a balloon sidewall makes it impossible to inflate the balloon, while the presence of thinned weakened regions tends to result in thin weakened blisters which burst during inflation; and, in either case, the problem renders the balloon unsalable and useless for its intended purpose.